Big brain evolution: brain size and intelligence (Evolution)

by David Turell , Saturday, April 21, 2018, 15:42 (2406 days ago) @ dhw

dhw: First you say the brain does the planning (as if planning was not thought), you give the soul a location as if that negated its function as the source of thought, then you ask me to define implementation, which I do, and now you ignore all that to tell me what I have been telling you for months: we know the brain of sapiens has shrunk, and I am the one who has proposed that the shrinkage is due to the efficiency of complexification!

DAVID: Cro-Magnons show advanced thought shrinks a brain, not the opposite effect.

dhw: Cro-Magnons show that over the last x thousand years, the sapiens’ brain has shrunk. You have just agreed that it is material complexification (not immaterial thought) that shrinks the brain, and complexification, as modern science has demonstrated, is caused by IMPLEMENTATION of thought.

Another misinterpretation of my thought. Our brain shrunk exactly because of new complex intensive immaterial thought, which drove the complexification to cause shrinkage. You cannot separate the two.

dhw: But by focusing on shrinkage, you are ignoring the whole context of our discussion, and so yet again let me try to summarize the context and the sequence from expansion to shrinkage:

1 Facts: a) pre-sapiens’ brain expanded; b) sapiens’ brain has shrunk; c) implementation of thought causes brain changes (complexification and limited expansion) in sapiens; d) sapiens’ thought has made major advances during the last x thousand years.

Not 'limited expansion' but 150cc shrinkage.

dhw: 2 You agree a) that in dualism the “soul” (software) does the thinking and interacts with the brain/body (hardware), which does the implementing; b) complexification has caused shrinkage in sapiens.

Because of intensive new thought/

dhw: 3 dhw’s dualistic hypothesis: a) pre-sapiens “soul” thinks up new concept; implementation of concept requires additional brain cells and connections. Brain expands; b) brain/skull reach maximum practical size in sapiens; “soul’s” thoughts now implemented by complexification and limited expansion of particular sections; c) process of complexification so efficient that sapiens’ brain no longer needs certain cells and connections, and shrinks.

Your theory is some not very complex thought, as compared to ours, in early hominins explodes the brain and with it the skull to larger size. Is this an explanation for speciation?

dhw" 4 All advances in thought must begin with individuals. Every stage in pre-sapiens human evolution continued for hundreds of thousands of years without significant advances until someone came up with new ideas which required brain change (expansion). Sapiens continued for hundreds of thousands of years until someone came up with new ideas which required brain change (see 3 b and c). The pattern is consistent.

Consistent only in your thinking. Pre-sapiens dealt with survival skills, not complex thought. They were little different than the wild animals we see today. The larger brains that appeared with each new advanced species produced more advanced artifacts. Artifacts require planning thought that only a bigger brain could supply through its s/s/c. And then implement the production of them. This pattern is consistent with history.